The present invention relates to a machine translation system for processing a sentence of a first language to obtain a translated sentence of a second language different from the first language and, more particularly, to a machine translation system with high operability, which easily selects translation results of an original sentence and corrects the selected translation result.
In recent years, machine translation systems for automatically processing an input original sentence by using a computer to obtain the translation have received a great del of attention. In a conventional machine translation system, the morpheme, structure, and/or other components of an input original sentence are analyzed so as to divide the original sentence into predetermined translation processing units. A translation dictionary is accessed for every translation processing unit in order to obtain words or phrases in a second language corresponding to the processing unit. The readout words and/or phrases are connected and/or arranged in accordance with predetermined grammatical rules so as to obtain a translated sentence.
However, since written works input into a machine translation system contain native idioms and the like, and a technique for completely analyzing their meanings has not yet been established, it is very difficult to obtain reliable and appropriate translated sentences. For this reason, in the conventional machine translation system, a plurality of translation possibilities are presented to a user (i.e., an operator) when an original word or phrase has more than one possible translation. The operator selects the most appropriate one of these possibilities and the selected possibility is output as the translation. Adverbs or adverbial phrases in a translated sentence which may be grammatically arranged at any one of a plurality of positions in the sentence are displayed in different positions, and the most appropriate one is selected by the operator.
Basically, translation possibilities are selected in the following way. If a word has different meanings, one of these meaning is selected. If it possibly modifies two or more words or is possibly modified by two or more words, one of these words is selected. If it can be used as two or more parts of speech, one of these parts of speech is designated. In most cases, one meaning of the word is closely related to one particular word or words modifying the word or modified by the word and is identified by the part of speech of the word. Hence, the translation possibility selected first for a first word often reduces the number of translation possibilities for a second word which is syntactically and semantically related to the first word. For example, once the part of speech has been designated for one word, one of the words which possibly modify this word or are modified by this word is automatically selected. This automatic selection often turns out to be an error, and this is one drawback of the machine translation system.
In order to prevent such a drawback, a user, who fully understands the translation processing function of the system and has sufficient knowledge of the language of the translated sentences can select an appropriate translation possibility. However, it is not practical to require all user to have full understanding of the translation processing function and the language of the translated sentences. Even if a user has this knowledge, as long as the translation system depends on the user's knowledge, operability of the system cannot be improved and the system cannot carry out its designed function.